air in fuel line of p38 ?

hi iam getting air in the fuel line of my p38
when idling to 2500rpm there is air bubbles traveling to the
engine from the fuel filter side clear pipe,when i give full throttle she
struggles to keep going and the pipe is frofy or no fuel at all
and she cuts out. i took the fuel line off the tank side of the filter while she was idling there is fuel coming out but not very fast not sure if this is norm, does anyone have any ides please
thanks
simon

I would start with the search facility. This subject has been covered more times than I care to remember. I would look to the in-tank pump or starters.